Figure 3.

Focal cluster distribution along the cell-fiber interface as a function of selected diameters. (a–c) Optical images of cells being pulled on 250-, 400-, and 800-nm-diameter fibers, respectively, with the two primary peripheral clusters (black arrows) shown distinctly from intermediary groups (white arrows), which increase with increasing diameter; (d–f) fluorescence images showing paxillin signal presence along the cell-fiber axis; and (g–i) corresponding intensity of the paxillin signal with primary cluster zones separated from intermediary zones by black dashed lines. As fiber diameter increases, signal intensity within this region increases as well (scale bar, 25 μm; n = 42). To see this figure in color, go online.